Apparatus for handling cans during processing



Oct. 22, 1929.

, c. H. PLUMMER APPARATUS FOR HANDLING CANS DURING PROCESSING Filed July 8, 1926 INVENTOR.

ATTORNEYS,

Patented Oct. 22, 1929 cmnnncn n. PLUMMER, OF xnwnunnn, WISCONSIN APPARATUS FUR HANDLING CANS DURING PRDGE SSING Application filed July 8,

This invention relates to apparatus for handling cans during processing.

It is well understood that canned goods are heat treated or processed in order to sterilize their contents. The processing operation ordinarily involvesthe introduction of a sealed can into a cooker to which live steam is admitted. The period for which the can is exposed to the steam varies in accordance with the size of the can and the nature of the food products sealed therein. The fact that the food products are hermetically sealed within the can ensures against the admission of bacteria to the can subsequentto the processing operation.

It has heretofore been considered extremely diflicult to manufacture a commercially acceptable package of processed food in large cans. In most instances a high proportion,

and in manycases, practically all of the largeremedy this situation and elaborate precauture and pressure are avoided.

tions have in some instances been taken to control the pressures in the cooking chamber during and subsequent to the processing op eration, whereby sudden changes in tempera- While such precautions have produced fairly satisfactory results they have not entirely overcome the difiiculty, and furthermore, are expensive in practice. p

It is the primary object of this invention to provide novel and simplified means for entirely overcoming the Warping or distortion of cans during the processing or heat treatment of food products hermetically. sealed therein. I have discovered the cause of the distortion occurring in the side Walls of the ans, and it is the purpose of the present invention to provide means for eliminating this cause. I

I have found that the Cylindrical side wall of a can is able to withstand easily all pressures developed within the can during the processing operation. Since the pressure is equal and uniform in all directions, the cylindrical side wall is not subject to such strains 1926. Serial No. 121,157.

as would cause it to become distorted. When the contents of the can are heated, however, they expand and develop high pressures within the can. The end walls of the can are Hat and are not adapted to Withstand such high pressures, and accordingly, they become bowed outwardly and thus enlarge the capacity of the can. Then when the can is cooled and the products therein are caused to contract, it will be obvious that unless the end walls of the can are restored to their original planes, the increased capacity of the can will result in the production of sub-atmospheric pressures therein.

It has been my experience that the outwardly bowed end walls of the can seldom return to their original positions. Being outwardly bowed they are, in effect, re entorced by their shape and they resist any tendency to press them inwardly. Differential pressures exerted inwardly upon the walls of the can, however, are such as to cause the cylindrical side wall of the can tocollapse at some point. Thus, a large proportion of the cans holding five pounds or more of food products are received from the processing operation with dents in their sides. These dents are frequently very deep and extend transversely oi the can. It is my discovery that the whole trouble is due to the increase in can capacity which occurs when the ends of the can become outwardly bowed as the temperature in the processing chamber increases. Accordingly, it is my purpose by the present invention to prevent the ends of the can from bowing outwar-dly. Thereby I maintain the can at a constant capacity and when the can is again cooled to atmospheric temperatures following the processing operation, pressures within and without such a can will again be equalized and there will be no distortion caused as aforesaid.

In the drawings Figure 1 is a vertical axial section through a kettle or processing chamber in which cans may be treated in accordance with this invention. Figure 1 is taken on a section indicated byline 1 -1 in Figure 2.

Figure 2 is a plan view of the kettle it appears when the cover is removed. Figure ice 2 is taken on a section indicated at 22 in Figure 1.

Figure 3 is an enlarged detail view showing means for keeping the ends of the can from becoming bowed.

Figure 4 is a side view of an individual can equipped with a form of band.

Figure 5 is a plan view of the retaining band applied to an individual can.

Like parts are identified by the same reference characters throughout the several views.

The chamber 5, which is commonly known as a kettle, is preferably made with a closely fitting cover 6 held thereto by wing nuts 7 which engage the ears 8 on the cover and are threaded to bolts 9 hingedly connected to the kettle 5.

Steam is supplied and condensate is drawn from the kettle by means of a stand pipe 10 disposed centrally in the kettle and provided at 11 with a valve controlling the degree of water to the drain pipe 12. A union at 13 connects the steam pipe 14 with the stand pipe 10. A valve 15 in the steam pipe controls the admission ofsteam which, it added, may be led upwardly within the stand pipe by the tube indicated in dotted lines at 16.

" The kettle as thus far described corresponds'quite closely to those which are now in use. In accordance with this invention, I add to such a kettle means which is not only adapted to support cans therein but is adapted to maintain the ends ofsuch cans in their original planes whereby to prevent distortion. It the ends of the cans are. flush with the margins of the side wall of the cans the problem is comparatively easy since it is only necessary'to confine the cans between plane surfaces. Ordinarily, however, the'ends of the cans are recessed as best shown in Figure 3, in which the side wall of a can is shown at 20andthe end Wall is shown at 21. It will be noted that the end wall is fixed to the side wall'by means of an annular flange 22 on the end wall, which is fitted Within the marginal portion of the side wall of the can and is there secured as by soldering or in any other convenient manner. Thus, the outer margin of flange 22 and the corresponding outer margin 23 of the side wall 20 of each can extends ax- I ially ofthe can for some distance beyond the normal plane of the end wall 21.

In order to support the end wall of such cans as are herein illustrated I provide blocks 25 in the bottom of the receptacle 0r kettle 5,

' each block being of a size to be received with in the flange 22 and having a plane end surfaceadapted to abut and support the end 21 of a can 17 These blocks are so postioned as to hold annular series of cans so positioned in close proximity as to cover the bottom of the cooker or kettle 5. I

Immediatelyabove the first tier of cans 17, which are disposed in the bottom of the kettle, is a spider 27 constructed something in the and chord-like members comprising the I spider carry blocks 28 on their upper surfaces and blocks 29 in corresponding or registering positions on their under surfaces. The blocks 29 are each positioned to enter fiange 22 and engage the end wall 21 at the upper end of a can in the lower tier within the kettle. Thus, the spider is supported on the lowest tier of cans and its blocks 28 are positioned to receive and support the ends of a second tier of cans which is likewise arranged in annular series corresponding to the arrangement of the first tier. Any desired number of tiers of cans and interposed spiders may be used to fill the receptacle or kettle 5.

It is desired, however, that the blocks receiving pressure from the uppermost tier of cans shall be engaged in pressure transmitting relation with the under surface of the cover 6 so to transmit directly to the cover the expansive tendency of the several tiers of cans.

It will be obvious that in the arrangement described, the kettle 5 with its cover 6 is adapted to receive through the successive tiers of cans and the interposed spacing or filler members constituting spiders 27 and blocks 28 and 29, the entire pressure exerted on the end walls of the cans by reason of the tendency for the contents of the can to expand when heated. As above stated, I have found that the side walls of some of the cans are amply able to resist outward pressures without becoming distorted. Consequently, by merely resisting the tendency for the ends of the can to bow outwardly, I am enabled to preserve the capacity of the can constant during its heating and cooling, and as a result of preserving the capacity constant it will be obvious that the ultimate pressure within the can will be the same at atmospheric temperatures as was the case when the can was filled at such temperatures. Therefore, there will be no tendency for the can to collapse after being cooled.

By way of summary it may be repeated that the process or method embodying this inveution is practiced by-mechanically supporting the end walls of the can while the can is sub ject to temperatures in excess of normal atmospheric temperatures. Thereby the ends of the can are prevented from bowing outwardly under pressures induced by the heating of the contents of the can and, consequently, the capacity of the can is maintained constant so that there is no tendency for the can to collapse when its contents contract to their normal state at atmospheric temperatures.

' In the practice of this invention it is entirely immaterial what gaseous pressures are maintained within the kettle 5 during the heating or cooling of the cans. Within the strength limit of the walls of the cans itis tle and its cover, whereby the ends of the cans also immaterial what temperatures are used of said tiers Wlll be secured against outward and how quickly these temperatures are expansion during such treatment.

changed. Although I have found that lapseam cans have adequate strength in their side walls to withstand any reasonable pres sure created in the process cooker, there are types of cans using joints which may not be adequate in strength and I therefore apply a quickly operated clamp which may be applied to each can as shown in Figures 4 and 5 before the can is placed in the kettle. The band may be placed about the body of the can midway between its ends and the hook 34 may be rotated about its axis 32 so as to throw the point 81 of the hook under the retaining loop 33 so as to draw the ends of the band tightly about the body of the can.

I claim:

1. In a device of the character described, the combination with a kettle adapted to re-- ceive canned goods for heat treatment, of means within said kettle operative to engage and confine against outward expansion the ends of a can to be treated.

2. In a device of the character described, the combination with a kettle adapted to receive canned goods for heat treatment, of can engaging means including blocks adapted to engage the opposing recessed ends of cans to be treated. I

3. In a device of the character described, the combination with a kettle adapted to receive canned goods to be heat treated, of can spacing means in said kettle including spiders adapted to be interposed between successive tiers of cans and provided with surfaces complementary to the ends of such cans, whereby to engage a suliicient area of the end of each can to prevent it from bowing outwardly.

a. In a device of the character described, the combination with a kettle adapted to receive canned goods for heat treatment, of a series of spiders adapted to be interposed be tween successive tiers of cans and each provided with blocks adapted to fit the recessed ends of cans in said tiers, said kettle being arranged to provide means for clamping said tiers and spiders in operative engagement, whereby to prevent the ends of cans in said kettle irom bowing outwardly under pressures developed during such treatment.

5. In a device of the character described, the combination wita a kettle adapted to re ceive canned goods for heat treatment, of means in said kettle for supporting the bottoms a first tier of cans therein, and a spider adapted to be interposed between said first tier and a second tier and provided with block portions complementary to the ends of the cans of such tiers, said kettle being provided with a cover and being; of such a length with reference to the number of tiers it is adapted to hold that said tiers and interposed spider will fit closely between the bottom of said ket- CLARENCE H. PLUMMER. 

